This invention relates to pumps for pumping breast milk.
Nursing mothers frequently use mechanized pumps to express milk from their breasts for bottle-feeding their infant children. Some such pumps are manually operated, in that the pumping action is motivated by reciprocating a piston or lever by hand, or compressing a flexible bulb. Often the pump lever is located directly on a structure that must be held against the breast while the lever is reciprocated. Other such pumps are electrically operated, and are generally considered less fatiguing than manual pumps. Between uses, careful cleaning is required to keep the pump components that come in contact with breast milk sanitary.
Pumped milk must typically be refrigerated if it will not be immediately consumed. It is common to store such milk in sanitized bottles or bags. Improvements to pump constructions and pumping methods are desired, for comfortable and sanitary use.
According to one aspect of the invention, a manual breast pump includes a suction bell having an internal suction chamber, a breast shield extending from the suction bell for receiving a human breast, and manually operable pumping lever secured to the suction bell for generating a cyclical vacuum within the suction chamber. The pumping lever is repositionable to multiple orientations with respect to the breast shield, and can be operated in each of the orientations to generate suction chamber vacuum.
Such breast pumps may be configured to assume multiple configurations, allowing the user to select from among different orientations of the pumping lever with respect to the breast shield for creating a cyclic vacuum condition within the suction chamber of the breast pump. For example, the pump can permit different orientations that allow the user to switch between the use of her right and left hands during a given breast pumping session.
In some embodiments, the lever is attached to a fulcrum repositionably secured to the suction bell.
In some cases, the fulcrum is secured to a collar that is rotatably secured to the suction bell. In some such pumps, the suction bell and collar together define a positioning detent that secures the lever in at least one of the multiple orientations of the lever with respect to the breast shield.
In some embodiments of the pump, the collar is secured to the suction bell by tabs extending from the collar and lodging in an annular channel on the suction bell, allowing the collar to be rotated in the manner of a dial with respect to the suction bell. In some such pumps, cutouts in the suction bell channel allow the tabs of the collar to lodge within the channel.
In some embodiments, the breast pump contains a flexible diaphragm attached to the suction bell such that it is in hydraulic communication with the suction chamber. In some such pumps the lever can be connected to the flexible diaphragm for creation of the cyclical vacuum. In some cases, the lever is connected to a rigid plunger which in turn is attached to the flexible diaphragm. In some configurations the diaphragm is removable from the suction bell, and in some of those pumps the diaphragm is attached to a separate pumping bell that is itself removably attached to the suction bell. In some cases, the diaphragm is attached to a pumping bell and defines a pumping chamber that is in hydraulic communication with the suction chamber of the suction bell. Threads are provided on the pumping bell, in some instances, to cooperate with threads on the suction bell to secure the pumping bell to the suction bell, which threads in some pumps comprise a quarter-turn fastener.
In some embodiments, a tortuous conduit hydraulically connects the pumping and suction chambers. In some such pumps, the tortuous conduit is defined by external surfaces of the pumping and suction bells, a perforation in the pumping bell, and a perforation in the suction bell.
In some cases, the lever is operably connected to a piston, which piston is slidably disposed within a cylinder, which cylinder is in hydraulic communication with the suction chamber. Some such pumps include a flexible ring between the piston and the cylinder wall for providing a slidable seal.
In some pumps, the lever is secured to the suction bell such that suction chamber pressure decreases in each cycle with a forward motion of the lever, and increases in each cycle with a return motion of the lever.
In some cases a valve, adapted to drain pumped milk from the suction chamber, is attached to the suction bell. A milk receptacle is removably secured to the suction bell beneath the valve in some such pumps. And in some instances, the valve is configured to restrict flow into the suction chamber as pressure in the suction chamber is lowered by pumping. Preferably, the valve is configured to drain pumped milk from the suction chamber when weight of milk above the valve exceeds a predetermined amount with vacuum pressure released. The valve in some cases is a duckbill valve.
In some configurations, the suction bell has an outer surface that defines a recess, on a side of the suction bell opposite the pumping lever. In some such pumps, this recess, together with the pumping lever, defines a manual grip that a user can cyclically squeeze to operate the pump. In some cases the recess is a neck in the suction bell, and in some of those pumps the pumping lever is shaped to conform to the neck. Preferably, the manual grip has a grip width changing less than one inch (more preferably, less than xc2xe of an inch) as the lever moves from a fully extended position to a fully retracted position.
Preferably, two of the multiple orientations define an adjustment range angle of at least forty-five degrees, more preferably, at least ninety degrees, and even more preferably, at least one-hundred and eighty degrees. In some cases, multiple positioning detents are defined between the lever and the suction bell, each detent corresponding to one of the multiple orientations.
According to another aspect of the invention, a breast pump includes a suction bell having an internal suction chamber, a breast shield extending from the suction bell for receiving a human breast, a valve attached to the suction bell that partially defines the suction chamber and is adapted to drain pumped milk from the suction chamber, and a removable, flexible liner, extending from within the breast shield, through the suction chamber, and out of the suction chamber through the valve, and defining a conduit for conducting pumped milk.
In some cases, the liner conducts pumped milk from the breast shield, through the suction chamber, and out of the suction chamber through the milk drainage valve for storage, while at the same time preventing contact between the pumped milk and those, and other, parts of the pump during normal operation. This can advantageously prevent parts of the pump other than the liner from contacting milk flow, simplifying cleaning and sterilization.
In some cases, the valve is configured to restrict flow into the suction chamber as pressure in the suction chamber is lowered by pumping. In some instances, the valves is a duckbill valve with one rigid bill and one flexible bill. Preferably, at least one bill is rigid and fixed in relation to the suction bell.
In some embodiments, the suction bell can be opened at a hinged joint to expose the suction chamber for liner insertion.
In many instances the pump is manually operable. For example, some embodiments have a manually operable pump lever secured to the suction bell for the user to generate a cyclical vacuum within the suction chamber.
In some cases, the liner defines a pouch external to the suction chamber for containing pumped milk. Some liners include a frangible section for separating the pouch from a remainder of the liner for milk storage. In some instances, the liner includes a pouch seal below the frangible section, for sealing milk within the pouch for milk storage. The pouch seal includes, in some instances, mating rib and groove fastener sections.
Preferably, the liner extends to a distal rim of the breast shield. Preferred liner materials include low-density polyethelyne, for example.
According to still another aspect of the invention, a breast pumping device has a suction bell with an internal suction chamber, a breast shield extending from the suction bell and defining a receptacle for receiving a human breast, a hand-operable lever secured to the suction bell for a user to generate a cyclical vacuum within the suction chamber, a secondary vacuum cycling pump in hydraulic communication with the suction chamber through a length of flexible tubing, and a valve for switching between a hand pumping mode and a secondary vacuum cycling pumping mode. The valve is repositionable between a first position that restricts hydraulic communication between the secondary vacuum cycling pump and the suction chamber, and a second position enabling hydraulic communication between the secondary vacuum cycling pump and the suction chamber, for switching between a hand pumping mode and a secondary vacuum cycling pumping mode of the device.
Advantages of such a breast pump may include ready switching between a manual pumping mode and another pumping mode, such as in which an external pumping source (e.g., an electric pump or a foot-operated pump) is connected to the suction bell and provides the cyclical vacuum necessary to induce lactation.
Some such pumps include a first port for attaching to the flexible tubing so that when the valve is positioned at its second position and the flexible tubing is attached to the first port, the secondary vacuum cycling pump will in hydraulic communication with the suction chamber through the flexible tubing. And in some embodiments, the mechanical and hydraulic connection between the flexible tubing and the first port is accomplished through a fitting positioned between and attached to the flexible tubing and the first port.
In some embodiments, the valve is repositionable between a first position, a second position, and a third position, with the suction bell defining a second port for attaching to the flexible tubing, through which, when the valve is positioned at the third position and the flexible tubing is attached to the second port, the secondary vacuum cycling pump is in hydraulic communication with the suction chamber. In some such cases, a fitting is positioned between and attached to the flexible tubing and the second port. And in some such pumps, the first and second ports are oriented in opposite lateral directions. Preferably, the first and second ports are located on opposites sides of the suction bell from the perspective of the breast shield.
In some embodiments, the port-selection valve has a body, a portion of which is disposed within the suction bell and at least partially defines a conduit through which the secondary vacuum cycling pump and the suction chamber hydraulically communicate.
In some instances, the lever is secured to the suction bell for cyclical motion by the user in which suction chamber pressure decreases in each cycle with a forward motion of the lever, and increases in each cycle with a return motion of the lever.
In another aspect of the invention, the change in grip width of a breast pump, as measured from when the pumping lever is in its fully extended position to when the pumping lever is in its fully retracted position, is less than about three-quarters of an inch. Such an optimally low grip width change may provide increased comfort for women pumping milk from their breasts and reduce fatigue during manual pumping operation.
According to another aspect of the invention, a manual breast pump includes a suction bell defining an internal suction chamber and a pumping chamber, the suction and pumping chambers being in hydraulic communication via an aperture through an internal suction bell wall, the aperture positioned at an upper end of the suction chamber. The pump has a breast shield extending from the suction bell and defining a receptacle for receiving a human breast, with the receptacle being in hydraulic communication with the suction chamber via a port disposed below the aperture. A valve forms a lower extent of the suction chamber and is constructed to both inhibit air flow into the suction chamber and to drain pumped milk from the suction chamber. The pumping chamber forms a manually cyclable volume, such that when the pumping chamber is expanded a vacuum is created in the suction chamber, and when the pumping chamber is subsequently collapsed the vacuum is reduced. Notably, the aperture provides hydraulic communication between the pumping and suction chambers only through a tortuous air flow conduit requiring multiple flow direction changes between the pumping and suction chambers.
In some embodiments, one side of the pumping chamber is defined by a movable diaphragm that is operably connected to a manually displaceable pumping lever.
In some cases, the pumping chamber is defined within a cup-shaped cavity in the suction bell, with the cavity containing a diaphragm that generally conforms, in a relaxed state, to the shape of the cavity. The aperture and air flow conduit are preferably disposed at a lower extent of the cavity.
In some constructions, the air flow conduit comprises an annular channel within the internal suction bell wall, with the annular channel in communication with the suction chamber at one rotational position along the channel via the aperture, and in communication with the pumping chamber via a port extending from the channel at another rotational position. Preferably, the rotational positions along the channel corresponding to the aperture and the hole are disposed at least 180 degrees from one another.
In some embodiments, the suction bell comprises a main bell body defining the suction chamber, and a bell insert defining the pumping chamber, the main bell body and bell insert cooperating to form the tortuous air flow conduit.
In some cases, the internal suction bell wall extends generally horizontally across an upper extent of the suction chamber.
This aspect of the invention can, in some cases, advantageously inhibit the flow of expressed milk from the suction chamber, which is readily cleaned between uses, into the pumping chamber to contaminate pumping components.
In still further aspects of the invention, methods are provided for pumping breast milk. Such methods feature placing the breast receptacle of one of the above described breast pumps against a woman""s breast and operating the breast pump to express milk from the breast.
The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.